New Zealand shares edged higher as growing violence in Iraq kept markets nervous and as local investors mulled a spate of new initial public offerings. Xero paced the gains after it said annualised sales eclipsed $100 million.

The NZX 50 Index rose 8.292 points, or 0.2 percent, to 5178.8. Within the index, 28 shares rose, 13 fell and nine were unchanged. Turnover was a smaller-than-usual $94.9 million.

Stocks across Asia were mixed as increasing violence in Iraq, where Prime Minister Nouri al-Maliki is seeking to regain territory held by the breakaway al-Qaeda group, Islamic State in Iraq and the Levant, has markets nervous OPEC's second biggest producer of crude oil may plunge further into conflict. Japan's Nikkei 225 Index fell 1.3 percent in afternoon trading, while Hong Kong's Hang Seng Index declined 0.1 percent and Australia's S&P/ASX 200 Index advanced 0.1 percent.

"Until things are sorted out in Iraq, and it's not going to be a quick fix, it will remain a concern. It will affect oil prices which affects every economy in the world so no one is isolated from the Iraqi situation," said Grant Williamson, director at Hamilton Hindin Greene. "Unfortunately investors are getting very much used to these sort of conflicts over in the Middle East and even Eastern Europe."

Xero climbed 0.6 percent to $29.31 after the cloud-based accounting software firm said it hit annualised sales of $100 million for the first time in May as monthly recurring subscription revenue rose to $8.6 million.

Fletcher Building dropped 0.5 percent to $8.93 after New Zealand's largest listed company said it faces an $11 million charge on the sale of its Australian-focused construction materials distribution business Hudson Building Supplies for $20 million to HTH Stores, after acquiring the business in 2011 when it took over the Crane Group.

Stock market operator NZX advanced 0.8 percent to $1.30 after more companies announced plans to list.

Hirepool, New Zealand's largest general equipment hire company, said it plans to raise as much as $262 million in an initial public offering and list on the Australian and New Zealand stock exchanges next month with a market capitalisation of as much as $340 million. Pushpay, the mobile payment app developer, said it will raise $9 million in a private share issue before it seeks a compliance listing on the New Zealand Alternative Index in July.

Serko, the online business travel booking company, closed the retail portion of its share offer nine days early last week and said it may scale back public share requests after strong investor demand. It is expected to debut on the NZX on June 24. Utilities and airport software developer Gentrack will list on June 25 in a $99.1 million IPO, selling shares at $2.40 apiece.

"With the spate of IPOs that are on the table at the moment, we may see one or two stocks weaken a little bit as investors look to liquidate funds to pay for the IPOs," Williamson said.

NZX launched it equity derivatives trading today, allowing investors to bet on the future pricing of the NZX 20 Index. Eight lots were traded for the July contract, which was last at 4010.

"There used to be a reasonable market in New Zealand for derivatives, but it is really just kicking off again so it's going to be a very long term project, you're not going to see significant volumes, what you're going to need to see is market makers to take positions on either side in order to create the market," Williamson said.